Got this from either "Muzzleblasts" or "Muzzleloader" a couple of years ago. A knapping tool made from a 16p nail. The point is cut off, and then, about a half inch back, a shoulder is cut in for about half the diameter. I rest the shoulder on the edge of the flint, in the gun, and tap, gently with the ball of my short-starter, or my knife handle....I was getting less than 20 shots per flint before finding this, now get up in the 40 or 50 shot range. I've made a few of these for friends, and have lately started using the old fashioned "cut nail" masonry nail...the flat sided one? looks almost as if a blacksmith had made it.
As the earlier poster said, when I work on the flint in the gun, no priming, touch hole blocked...muzzle down range, just in case...Hank